Application Ser. No. 181,445 of which this is a continuation in part, discloses a pulse generator circuit wherein the entire voltage across one winding of an oscillator circuit is used as negative feedback to prevent unwanted oscillation under specific conditions of coupling between windings in said oscillator. That circuitry allowed use of a generally U-shaped or C-shaped core with a vane interrupting this core structure at only one point. As pointed out in that application this offered considerable advantages over previous vane controlled oscillator circuits. The purpose of the present invention is to retain the advantages of that invention while at the same time reducing the number of non-grounded leads leading from the distributor (or the portion of the oscillator circuit required to be in the distributor) to one, while also eliminating all taps or intermediate connection points on windings within the distributor unit. In one embodiment of the present invention one winding is the only component required to be in the distributor. It is another object of this invention to further decrease the sensitivity of the circuitry to both input voltage and temperature. A thorough understanding of the concepts disclosed and described in U.S. Pat. No. 3,837,325 will be necessary for a proper understanding of what is to follow in this application since concepts disclosed and described therein will not be herein repeated.
In said previous application and in the previous patents refered to therein, the amplifying device has been biased in the active region at a constant current, generally produced by the combination of a resistor and the emitter circuit of the amplifying device and a reference voltage such as produced by a stabistor in the base circuit. In the present invention the equivalent amplifying device is operated as a constant voltage but variable current device. The collector emitter bias voltage is held at, or very near, the base emitter saturation voltage for the transistor (typically about seven tenths of a volt for a silicon device). Because of the low voltage, the dissipation in the amplifying device is held to a low level and satisfactory operation of the stage has been observed over a range of from one to forty volts DC supply voltage.